1. Field of the Invention
This invention is a timer device to control the time of operation of a television set, or other electric appliance. It is token activated, as tokens inserted into the device allocate time credit. When the allocated operating time has expired the appliance is turned off.
A control function for television is desireable in certain circumstances for economic or social reasons. It is a common practice to sell television time in closed circuit systems in locations such as hotels or airports. In the home the amount of time children spend watching television, or engaged in television related activities such as video games, can be a source of arguments between parents and children with parents wanting children to spend more time on schoolwork or physical activities.
A major problem with television time regulation systems that has not been addressed by prior art systems is the child's resentment at losing some of his independence regarding television time. The present invention is designed to minimize this resentment. It is based on a token allocation system. A child is allocated a number of tokens corresponding to an amount of television time at the beginning of a given time period, say one week. During that week the scheduling of television time is completely under the control of the child. The parent does not become involved again until the beginning of the following week. Another feature of the present invention to maximize the child's acceptance of the device is an audible alert a convenient time, such as two minutes, before television time is terminated. The intent of the audible alert is to avoid unexpected cut-off of television operation.
2. Discussion of Prior Art
Pertinent prior art includes U.S. Pat. No. 4,588,901 to Maclay et al., May 13, 1986. There are a number of improvement differences offered by the present invention over the Maclay device.
Maclay invention uses a multi-contact keyswitch to input time credit information to the device. The present invention uses tokens to input time credit information to the device. The purpose of the token system is to maximize the effectiveness of the television time regulation function by maximizing the child's acceptance of it as explained in BACKGROUND-FIELD of INVENTION and OBJECTS and ADVANTAGES. A minor disadvantage of the token system is a larger vertical dimension required for the device case.
The present invention differs from the Maclay device in that the present invention has an audible alert a few minute before television operation is terminated in order to warn the child that his television time will soon be up.
In the Maclay device the counter measuring time of operation of the controlled electric appliance is turned on or off depending on the amount of electrical current flowing to the appliance. This is not a reliable method of operation as some appliances conduct standby current. Standby current is electric current to the appliance when the appliance is off. The standby current of one appliance can be greater than the operating current of a second appliance, thereby making reliable operation of the Maclay invention impossible. The present invention uses an on/off switch on the device housing to turn the controlled electrical appliance on and off.
The Maclay device uses a triac as the main power switch component conducting or not conducting power to the television set. The present invention uses a relay.
Other prior art television timer devices in addition to the Maclay device are effective only on selected frequency channels (U.S. Pat. No. 4,821,862 to Nelson, Apr. 18, 1989) or do not have the capability to retain time credit when the television is turned off (U.S. Pat. No. 3,879,332 to Leone, Apr. 22, 1975).